UK H1N1 flu deaths reach 29; virus spreading fast

LONDON (Reuters) - Twenty-nine Britons infected with the H1N1 flu virus have died and officials have made plans to cope with nearly a third of the population falling ill, the health department said on Thursday.

A further 30 percent of the population may catch the virus without developing symptoms, the department said in a planning document published on its website.

"If the current growth in cases is sustained, a substantial wave of cases with up to 30 percent of the population experiencing symptoms could peak in early September," the document said.

However, it stressed that its figures were based on a "reasonable worst case" scenario to help health services to plan and were not a prediction.

There is a chance the virus' spread could slow during the school summer holidays before peaking in October after children go back to school, the document added.

"Hospitalizations have doubled in the last week," Britain's top medical officer Liam Donaldson told a news conference. "We cannot give an estimate of likely deaths for this virus, it is far, far too early."

The majority of the estimated 55,000 new cases of swine flu in Britain last week were mild. The under-5s and 5- to 14-year-olds are the age groups predominantly affected. Patients with pre-existing illnesses were most at risk of dying.

The World Health Organization said on Thursday that the flu pandemic was the fastest-moving pandemic ever and that it was now pointless to count every case.

The flu outbreak had killed 429 around the world by early July, according to the latest statistical breakdown published by the agency on July 6. The United States was the worst affected country, with 170 deaths, followed by Mexico on 119.

July 10 figures from the U.S. Centers for Disease Control and Prevention said the U.S. toll had now reached 211.

The virus was first detected in Mexico in April before spreading to the rest of the world, prompting the WHO to declare an influenza pandemic on June 11.

Britain has contracts for 132 million doses of flu vaccine and the health service is coping well with the outbreak, officials said.

Britain's Health Minister Andy Burnham said this month the government was projecting more than 100,000 new cases a day of the flu by the end of August.

(Additional reporting by Peter Griffiths; Editing by Alison Williams)